Increasing sea surface temperatures (SSTs) are predicted to adversely impact coral populations worldwide through increasing thermal bleaching events. Future bleaching is unlikely to be spatially uniform. Therefore, understanding what determines regional differences will be critical for adaptation management. Here, using a cumulative heat stress metric, we show that characteristics of regional SST determine the future bleaching risk patterns. Incorporating observed information on SST variability, in assessing future bleaching risk, provides novel options for management strategies. As a consequence, the known biases in climate model variability and the uncertainties in regional warming rate across climate models are less detrimental than previously thought. We also show that the thresholds used to indicate reef viability can strongly influence a decision on what constitutes a potential refugia. Observing and understanding the drivers of regional variability, and the viability limits of coral reefs, is therefore critical for making meaningful projections of coral bleaching risk.

预计通过增加热漂白事件，海面温度（SSTs）的升高将对全世界的珊瑚种群产生不利影响。未来的漂白不太可能在空间上均匀。因此，了解决定区域差异的因素对于适应管理至关重要。在这里，使用累积热应力度量，我们表明区域SST的特征决定了未来的漂白风险模式。结合观察到的SST变异性信息，评估未来的漂白风险，为管理策略提供了新的选择。结果，气候模型可变性的已知偏差和整个气候模型的区域升温速率的不确定性比以前认为的有害程度要小。我们还表明，用于指示礁石生存能力的阈值可以强烈影响对构成潜在避难所的决定。因此，观察和理解区域变化的驱动因素以及珊瑚礁的生存极限，对于做出有意义的珊瑚白化风险预测至关重要。